Mobile power bank



FIG. 1 is a schematic view of a power bank showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a left view thereof;

FIG. 5 is a right view thereof;

FIG. 6 is a top view thereof, and,

FIG. 7 is a bottom view thereof.

The broken lines in the drawings are for the purpose of illustrating portions of the mobile power bank that form no part of the claimed design. 

CLAIM The ornamental design for a mobile power bank, as shown and described. 